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20 results found

Bridging vessel sign

The bridging vessel sign refers to an appearance of vessels coursing from the uterus into an adjoining pelvic mass (a vascular bridge). This sign helps to differentiate a pedunculated subserosal uterine leiomyoma from other juxtauterine masses of ovarian, adnexal or bowel origin. Colour and pow...

Claw sign (mass)

The claw sign is useful in determining whether a mass arises from a solid structure or is located adjacent to it and distorts the outline. It refers to the sharp angles on either side of the mass, which the surrounding normal parenchyma forms when the mass has arisen from the parenchyma. As suc...

Cogwheel sign

The cogwheel sign refers to an imaging appearance in pelvic imaging of thickening loops of the Fallopian tube seen on cross-section. There are infolding projections (sometimes looking like nodules) into the Fallopian tube lumen which is likened to that of a cogwheel. The sign is typically descri...

Dot dash pattern

The dot-dash pattern (dermoid mesh) is one of the characteristic sonographic appearances of an ovarian dermoid cyst. It refers to the short and long echogenic lines which are often seen within a dermoid cyst and are due to the presence of hair.

Funneling of the internal cervical os

Cervical funnelling is a sign of cervical incompetence and represents the dilatation of the internal part of the cervical canal and reduction of the cervical length. Greater than 50% funnelling before 25 weeks is associated with ~80% risk of preterm delivery. Radiographic features Good scanni...

Mushroom cap sign

Mushroom cap sign is one of the important signs of deep rectosigmoid endometriosis seen on T2 weighted MRI sequence. It indicates the submucosal involvement in rectosigmoid region. Radiographic appearance MRI Hypertrophic muscularis propria appears as heterogeneous low signal intensity surrou...

Popcorn calcification

Popcorn calcification refers to amorphous calcifications often with rings and arcs that resemble popped corn kernels. This type of calcification may be seen in many radiological settings including 1: chondroid lesions (e.g enchondroma, chondrosarcoma) fibrous dysplasia pulmonary hamartomas d...


A pseudodysraphism refers to the splayed appearance of a normal spine created due to excessive craniocaudal angulation during sonographic evaluation. This can erroneously lead to the diagnosis of a spinal neural tube defect.

Ring of fire sign (adnexa)

The ring of fire sign, also known as ring of vascularity, signifies a hypervascular lesion with peripheral vascularity on colour or pulsed Doppler examination of the adnexa due to low impedance high diastolic flow 1. This sign can be seen in: corpus luteum cyst (more commonly) ectopic pregnan...

Rokitansky nodule

A Rokitansky nodule or dermoid plug refers to a solid protuberance projecting from an ovarian cyst in the context of a mature cystic teratoma. It often contains calcific, dental, adipose, hair, and/or sebaceous components 1. This region has the highest propensity to undergo malignant transformat...

Shading sign (endometrioma)

Shading sign is an MRI finding typically seen in an endometrioma. It may also be seen with some endometrioid tumours (e.g endometrioid carcinoma of the ovary) It helps to distinguish endometriomas from other blood-containing lesions (e.g. haemorrhagic corpus luteum cysts), with a sensitivity of...

Shortening of the cervical canal

Shortening of the uterine cervical canal as the name implies refers to an abnormal shortening of the uterine cervical length. It is considered a sign of cervical incompetence during pregnancy and can lead to premature delivery. Pathology Aetiology primary (i.e. congenital/idiopathic) seconda...

Snowstorm sign (disambiguation)

Snowstorm sign may refer to: snowstorm sign: complete hydatiform mole (ultrasound) snowstorm sign: extracapsular breast implant rupture (ultrasound) snowstorm sign: thyroid pulmonary metastases (chest radiograph)

String of pearls sign (disambiguation)

String of pearls sign can refer to: string of pearls sign on an abdominal radiograph of fluid-filled dilated small bowel loops string of pearls sign on ultrasound in polycystic ovarian syndrome string of pearls sign for angiographic appearances in fibromuscular dysplasia

T2 dark spot sign

T2 dark spot sign is an MRI appearance of endometriomas seen as a result of chronic haemorrhage. The sign is useful in differentiating a solitary endometrioma from a functional haemorrhagic ovarian cyst, as both might show high T1 signal with T2 shading.  The T2 dark spot, described in the sign...

Tip of the iceberg sign (ovarian dermoid cyst)

Tip of the iceberg sign refers to one of the characteristic appearances of an ovarian dermoid cyst. If there are echogenic cyst contents of sebum and hair, they cause marked posterior acoustic attenuation so that only the superficial part of the cyst is seen. Just like an iceberg, you may only b...

Tubal ring sign

Tubal ring sign, also referred to as bagel sign or blob sign, one of the ultrasound signs of a tubal ectopic. It comprises of an echogenic ring which surrounds an unruptured ectopic pregnancy. It is said to have a 95% positive predictive value (PPV) for ectopic pregnancy. Differential diagnosis...

Venetian blind artifact (uterus)

The Venetian blind artifact (shadows) is a sonographic finding that is typically associated with adenomyosis but can also occur in uterine fibroids. The Venetian-blind artifact associated with adenomyosis is typically "thin" whereas when associated with uterine fibroids, there are also edge shad...

Whirlpool sign (mesentery)

The whirlpool sign of the mesentery, also known as the whirl sign, is seen when the bowel rotates around its mesentery leading to whirls of the mesenteric vessels.  Terminology The term whirlpool sign is used in other contexts: see whirlpool sign (disambiguation). Radiographic features It is...

Whirlpool sign (ovarian torsion)

The whirlpool sign or whirl sign of ovarian torsion is characterised by the appearances of a twisted ovarian pedicle seen on US or even on CT.  Terminology The term whirlpool sign is used in other contexts: see whirlpool sign (disambiguation).

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